AISI 329 (S32900) Stainless Steel
AISI 329 stainless steel is a duplex stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the annealed condition. 329 is the AISI designation for this material. S32900 is the UNS number.
It has a fairly low ductility among wrought duplex stainless steels. In addition, it has a moderately high thermal conductivity and a fairly low electrical conductivity.
The graph bars on the material properties cards below compare AISI 329 stainless steel to: wrought duplex stainless steels (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Brinell Hardness
240
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
17 %
Fatigue Strength
330 MPa 48 x 103 psi
Poisson's Ratio
0.27
Rockwell C Hardness
24
Shear Modulus
80 GPa 12 x 106 psi
Shear Strength
440 MPa 63 x 103 psi
Tensile Strength: Ultimate (UTS)
710 MPa 100 x 103 psi
Tensile Strength: Yield (Proof)
540 MPa 79 x 103 psi
Thermal Properties
Latent Heat of Fusion
300 J/g
Maximum Temperature: Corrosion
450 °C 840 °F
Maximum Temperature: Mechanical
1100 °C 2010 °F
Melting Completion (Liquidus)
1440 °C 2620 °F
Melting Onset (Solidus)
1390 °C 2540 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
16 W/m-K 9.3 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.4 % IACS
Otherwise Unclassified Properties
Base Metal Price
16 % relative
Density
7.7 g/cm3 480 lb/ft3
Embodied Carbon
3.1 kg CO2/kg material
Embodied Energy
44 MJ/kg 19 x 103 BTU/lb
Embodied Water
170 L/kg 20 gal/lb
Common Calculations
PREN (Pitting Resistance)
30
Resilience: Ultimate (Unit Rupture Work)
110 MJ/m3
Resilience: Unit (Modulus of Resilience)
730 kJ/m3
Stiffness to Weight: Axial
15 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
25 points
Strength to Weight: Bending
23 points
Thermal Diffusivity
4.3 mm2/s
Thermal Shock Resistance
19 points
Alloy Composition
Among wrought stainless steels, the composition of AISI 329 stainless steel is notable for containing a comparatively high amount of chromium (Cr). Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance.
| Fe | 63.1 to 74 | |
| Cr | 23 to 28 | |
| Ni | 2.0 to 5.0 | |
| Mo | 1.0 to 2.0 | |
| Mn | 0 to 1.0 | |
| Si | 0 to 0.75 | |
| C | 0 to 0.080 | |
| P | 0 to 0.040 | |
| S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
Duplex Stainless Steels, Iris Alvarez-Armas and Suzanne Degallaix-Moreuil (editors), 2009
Duplex Stainless Steels: Microstructure, Properties and Applications, Robert N. Gunn (editor), 1997
ASTM A240: Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
Welding Metallurgy and Weldability of Stainless Steels, John C. Lippold and Damian J. Kotecki, 2005
ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels
Corrosion of Stainless Steels, A. John Sedriks, 1996
ASM Specialty Handbook: Stainless Steels, J. R. Davis (editor), 1994
Advances in Stainless Steels, Baldev Raj et al. (editors), 2010